| 摘要 |
PROBLEM TO BE SOLVED: To provide a copolyester resin which has excellent adhesive force to a fluororesin and a polyester resin constituting a back sheet in a solar power generation module, and which can be stably used for a long period of time with excellent heat and moisture durability.SOLUTION: In a polyester resin comprising an acid component and a glycol component, terephthalic acid and isophthalic acid are included as the acid component, and a total content of the terephthalic acid and the isophthalic acid is 60 mol% or more in the acid component. Neopentyl glycol, ethylene glycol, and 1,4-cyclohexanedimethanol and also polytetramethylene ether glycol are contained as the glycol component, and a content of the neopentyl glycol in the glycol component is 40 to 70 mol%, and the amount of a hydroxy group terminal group is 5 to 30 mgKOH/g, in a copolyester resin. |
